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How quickly can the human heart rate rise and fall?

How quickly can the human heart rate rise and fall?


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How quickly can the human heart rate rise and lower?

For example lets say a human heart rate is rested and is at 60BPM and that person is suddenly scared to trigger their fight or flight reaction. Lets say their heart rate rises to double (120BPM).

From the above example their rate has gone from 1000ms between beats to 500ms between beats. Can the human heart instantly in one heart beat go from the 1000ms to 500ms between beats or does it need to ramp up? If yes how quickly can the heart rate ramp up?

I understand that each human heart is different, and that the speed increase and decrease will be different from person to person. What I'm looking for is a value that I can safely say the human heart won't exceed.

Similarly the same question goes to your heart going lower.


According to the Wikipedia page on Supraventricular tachycardia the heart can go to a new faster rate in the space of a single beat, and then come down again just as quickly, as shown in this image taken from the Wikipedia page.


What is Entrainment and How Does the Human Body Respond to Rhythm?

Have you ever found yourself lost in conversation when walking next to someone, but then you look down and suddenly you notice that your footsteps are totally in sync? When they step with their right foot, your right foot is already moving to match the pace, in total coordination, without even thinking about it!

Well, falling into step with someone is one of the most obvious examples of a concept called entrainment.

Oxford English Dictionaries defines entrainment like this:

Biology (of a rhythm or something which varies rhythmically) cause (another) gradually to fall into synchrony with it.

In simple terms, it describes the way the body gradually syncs with either a biological or external rhythm.

The key thing about entrainment is that it can happen unconsciously. For example, when dancing you might be trying to move to the beat, but you might not realise that your breathing rate will also be syncing up.

Here are just some of the ways the human body can respond to rhythm - but let us know if you can think of any others!


Test Details

What is maximum heart rate?

The maximum heart rate is the highest heart rate achieved during maximal exercise. One simple method to calculate your predicted maximum heart rate, uses this formula:

220 - your age = predicted maximum heart rate

Example: a 40-year-old's predicted maximum heart rate is 180 beats/minute.

There are other formulas that take into account the variations in maximal heart rate with age and gender. If you are interested in learning more about these more accurate but slightly more complicated formulas please see these resources:

  • Gellish RL, Goslin BR, Olson RE, McDonald A, Russi GD, Moudgil VK. Longitudinal modeling of the relationship between age and maximal heart rate. Med Sci Sports Exerc. 2007 May39(5):822-9. www.ncbi.nlm.nih.gov/pubmed/17468581
  • Gulati M, Shaw LJ, Thisted RA, Black HR, Bairey Merz CN, Arnsdorf MF. Heart rate response to exercise stress testing in asymptomatic women: the st. James women take heart project. Circulation. 2010 Jul 13122(2):130-7. Epub 2010 Jun 28. www.ncbi.nlm.nih.gov/pubmed/20585008

Your actual maximum heart rate is most accurately determined by a medically supervised maximal graded exercise test.

Please note that some medications and medical conditions may affect your heart rate. If you are taking medications or have a medical condition (such as heart disease, high blood pressure or diabetes), always ask your doctor if your maximum heart rate/target heart rate will be affected. If so, your heart rate ranges for exercise should be prescribed by your doctor or an exercise specialist.

What is target heart rate?

  • You gain the most benefits and lessen the risks when you exercise in your target heart rate zone. Usually this is when your exercise heart rate (pulse) is 60 to 80% of your maximum heart rate. In some cases, your health care provider may decrease your target heart rate zone to begin with 50% .
  • In some cases, High Intensity Interval Training (HIIT) may be beneficial. This should be discussed with a healthcare professional before beginning. With HIIT exercise, heart rates zones may exceed 85%.
  • Always check with your healthcare provider before starting an exercise program. Your provider can help you find a program and target heart rate zone that matches your needs, goals and physical condition.
  • When beginning an exercise program, you may need to gradually build up to a level that's within your target heart rate zone, especially if you haven't exercised regularly before. If the exercise feels too hard, slow down. You will reduce your risk of injury and enjoy the exercise more if you don't try to over-do it!
  • To find out if you are exercising in your target zone (between 60 and 80% of your maximum heart rate), stop exercising and check your 10-second pulse. If your pulse is below your target zone (see below), increase your rate of exercise. If your pulse is above your target zone, decrease your rate of exercise.

What is your target zone?

Target Heart Rate Zones by Age *

  • Age: 20
    • Target Heart Rate (HR) Zone (60-85%): ** 120 – 170
    • Predicted Maximum HR: 200
    • Target Heart Rate (HR) Zone (60-85%): 117 – 166
    • Predicted Maximum HR: 195
    • Target Heart Rate (HR) Zone (60-85%): 114 – 162
    • Predicted Maximum HR: 190
    • Target Heart Rate (HR) Zone (60-85%): ** 111 – 157
    • Predicted Maximum HR: 185
    • Target Heart Rate (HR) Zone (60-85%): 108 – 153
    • Predicted Maximum HR: 180
    • Target Heart Rate (HR) Zone (60-85%): 105 – 149
    • Predicted Maximum HR: 175
    • Target Heart Rate (HR) Zone (60-85%): 102 – 145
    • Predicted Maximum HR: 170
    • Target Heart Rate (HR) Zone (60-85%): 99 – 140
    • Predicted Maximum HR: 165
    • Target Heart Rate (HR) Zone (60-85%): 96 – 136
    • Predicted Maximum HR: 160
    • Target Heart Rate (HR) Zone (60-85%): 93 – 132
    • Predicted Maximum HR: 155
    • Target Heart Rate (HR) Zone (60-85%): 90 – 123
    • Predicted Maximum HR: 150

    Your Actual Values (Actual Values are determined from a graded exercise test)

    * This chart is based on the formula: 220 - your age = predicted maximum heart rate.


    Once you've calculated the maximum heart rate for your age, you can proceed to figuring out your target heart-rate zone. According to the Cleveland Clinic, your target heart rate zone is between 60 and 85 percent of your maximum rate. Therefore, if you're 45 years old and have a maximum heart rate of 175 beats per minute, your heart should beat between 105 and 149 beats per minute while you exercise.

    A variety of factors can cause a rise or fall in your heart rate during exercise. Knowing these factors allows you to adjust your workout intensity to remain in your target zone. Hot weather can cause a spike in your heart rate, as can obesity and thyroid medication. Beta blockers, meanwhile, can cause a decrease in your heart rate. Certain body positions and especially a quick change in the position of your body can result in a temporary heart rate change.


    BioEd Online

    Overview

    Students measure their prior to conducting a variety of physical activities. After conducting the activities, they measure and compare their post-exercise heart rates to their resting heart rates. They also compare their heart rates to those of students in other groups.

    As part of this activity, students visit the PowerPlay exhibit at the Children's Museum of Houston. This lesson is best conducted before going to the Museum. Also, prior to the visit read "Teacher Tips," to plan the visit, and to learn about alternative options for conducting the activity without a Museum visit (see PDF).

    This activity is from the PowerPlay Teacher's Guide. Although it is most appropriate for use with students in grades 3-7, the lessons are easily adaptable for other grade levels.

    Safety Note: Do not have students use the carotid artery in the neck to find their pulse. Applying too much pressure there could stimulate a reflex mechanism that can slow down the heart. The radial pulse point is the pulse site recommended for the general public by the National Heart, Lung, and Blood Institute, National Institutes of Health.

    The PowerPlay project is a partnership between Baylor College of Medicine and the Children's Museum of Houston.

    Teacher Background

    Every day, it seems we hear or read about the importance of exercise for heart health. Why? What is the relationship among the heart, circulation, and exercise? The Children&rsquos Museum of Houston&rsquos PowerPlay exhibit is designed to teach young people about heart health and reinforce healthy behaviors, as students discover new ways to be physically active. While they progress through the exhibit, students will be able to track heart rate, measure strength, and examine performance levels. This activity will enable students to learn how their hearts respond to physical activity. It should be completed before they visit the Museum.

    Even when you are sleeping, reading, or watching TV, your body uses oxygen and nutrients, and produces carbon dioxide and other wastes. When you get up and start moving around, your body demands more oxygen and produces more carbon dioxide as waste. These demands increase even further if you start running or doing another strenuous activity. The circulatory system responds by raising the heart rate (how often the pump contracts) and stroke volume (the amount of blood pumped with each contraction) to increase the cardiac output (the volume of blood pumped from the left ventricle per minute). During exercise, heart rate can rise dramatically, from a resting rate of 60&ndash80 beats per minute to a maximum rate of about 200 for a young adult.

    A pumping heart makes the sound we call the &ldquoheartbeat.&rdquo The &ldquolub-dub&rdquo of a heartbeat is actually the sound of blood being pushed against the closed, one-way valves of the heart. One set of valves (tricuspid and bicuspid) closes as the ventricles contract. This generates the &ldquolub&rdquo of our heartbeat. A second set of valves (pulmonary and aortic) closes when pressure in the ventricles is lower than the pressure in the aorta and pulmonary artery. This produces the &ldquodub&rdquo of our heartbeat.

    As the heart beats, it forces blood from the ventricles into the muscular, elastic walls of the arteries, causing them to expand. Each artery wall then contracts to &ldquopush&rdquo the blood onward, further through the body. You can feel those &ldquopulses&rdquo of blood, moving through the arteries in rhythm with your heartbeat. The number of pulses per minute, usually referred to as pulse rate, is measured in beats per minute (BPM). The average pulse rate for a child ranges from 60 to 120 BPM.

    Objectives and Standards

    Texas Essential Knowledge and Skills (TEKS) Objectives

    Science

    Student uses scientific inquiry methods during laboratory and outdoor investigations.


    What your heart and brain are doing when you're in love

    (CNN) -- Poets, novelists and songwriters have described it in countless turns of phrase, but at the level of biology, love is all about chemicals.

    Although the physiology of romantic love has not been extensively studied, scientists can trace the symptoms of deep attraction to their logical sources.

    "Part of the whole attraction process is strongly linked to physiological arousal as a whole," said Timothy Loving (his real name), assistant professor of human ecology at the University of Texas, Austin. "Typically, that's going to start with things like increased heart rate, sweatiness and so on,"

    When you catch sight of your beloved and your heart starts racing, that's because of an adrenaline rush, said Dr. Reginald Ho, a cardiac electrophysiologist and associate professor of medicine at Thomas Jefferson University Hospital in Philadelphia, Pennsylvania.

    Here's how it works: The brain sends signals to the adrenal gland, which secretes hormones such as adrenaline, epinephrine and norepinephrine. They flow through the blood and cause the heart to beat faster and stronger, Ho said.

    The response is somewhat similar to a fast heartbeat while running on a treadmill, although exercise has other benefits, he said.

    For people with serious heart problems, love could actually be dangerous, Ho said. That's because when the heart rate goes up, the heart uses more oxygen, which can be risky for an older person with blood vessel blockages or who has had a prior heart attack. But good medicines such as beta blockers help curb the adrenaline response, Ho said.

    It is also likely that norepinephrine, a stress hormone that governs attention and responding actions, makes you feel weak in the knees, said Helen Fisher, professor at Rutgers University and author of the book "Why Him? Why Her? Finding Real Love by Understanding Your Personality Type."

    Fisher's research team did brain imaging of people who said they were "madly in love" and found activity in the area of the brain that produces the neurotransmitter dopamine. Dopamine and norepinephrine are closely related.

    "What dopamine does is it gives you that focused attention, the craving, the euphoria, the energy and the motivation, in this case the motivation to win life's greatest prize," she said.

    This norepinephrine response has never been precisely studied in relation to romantic love, but the system seems to be more activated in people in love, she said.

    Also likely involved is the serotonin system, she said. Some data from an Italian study indicate that a drop in serotonin levels is associated with obsessive thinking.

    The stress hormone cortisol has also been shown to have implications for love, Loving said. His lab showed study participants who had recently fallen in love a picture of a romantic partner or friend, and had them describe or "relive" the moment of falling in love or wanting to be friends, respectively. Those who recalled falling in love showed an increase in stress hormones such as cortisol even 30 minutes after they were asked to think about it.

    Generally, there are three brain systems involved in romantic love: sex drive, love and attachment, Fisher said. The sex drive evolved to get you to look for a lot of partners, the "love" portion is for focusing mating energy on one specific person at a time, and attachment is for allowing you to tolerate the partner -- at least, long enough to have children with him or her.

    These systems are often connected, but can operate separately, she said. That means you can start out with one of them -- casual sex, or an intense feeling of love, or an emotional connection -- and move on to the others. For example, what may start out as a one-night stand may feel like more because the hormones oxytocin and vasopressin, released during orgasm, make you feel deeply attached to someone. You may feel in love after that, or instead feel somehow responsible for the person, because of these hormones.

    Fisher's team has found that romantic love doesn't have to die -- they found the same activity in the brains of people who said they were in love after 20 years of marriage as in people who had just fallen in love. This brain area makes dopamine and sends it to other areas.

    In the days of early humans, in hunting-and-gathering societies, these qualities were especially advantageous for finding a person to bear and raise children with, she said.

    Why, then, do small children fall in love if they are not trying to reproduce? Fisher hypothesizes that kids -- even 4-year-olds -- practice at love and learning more about themselves before it begins to become important to them.

    Love also has health benefits for people who have aged beyond their reproductive years, she said. Being in love makes people feel optimistic, energetic, focused and motivated, which were all positive for health and societal contribution in the early days of humans, she said. So, it makes sense evolutionarily that people can still fall in love after their childbearing period.

    Romance also is good for you. Studies have shown that people who have frequent sex are generally healthier, with a longer life, fewer coronary events and lower blood pressure. A 1995 study in the journal Demography found that marriage adds seven years to a man's life and two years to a woman's.

    Loving's team is studying how people who have recently fallen in love respond to stressful situations. They hypothesize that people for whom the love is still new will respond to the stress and recover from it quicker than those who have recently been in a breakup or have been in a relationship for a long time.

    "The guess is that when individuals are falling in love, they are walking around with rose-colored glasses," he said.


    Causes of bradycardia

    Causes for bradycardia include:

    • Problems with the sinoatrial (SA) node, sometimes called the heart&rsquos natural pacemaker
    • Problems in the conduction pathways of the heart that don&rsquot allow electrical impulses to pass properly from the atria to the ventricles
    • Metabolic problems such as hypothyroidism (low thyroid hormone)
    • Damage to the heart from heart disease or heart attack
    • Certain heart medications that can cause bradycardia as a side effect

    How Can the Vagus Nerve Affect Heart Rate?

    The vagus nerve affects heart rate by increasing blood vessel dilation and lowering blood pressure, according to Healthline. Vagus nerve stimulation can cause a drop in blood flow to the brain and a loss of consciousness known as vasovagal syncope.

    The vagus nerve is a part of the body’s parasympathetic system it slows the heart rate and helps return the body to a state of calm after a stressful or threatening experience. It is also responsible for setting a person’s resting heart rate, explains the Sarver Heart Center. Higher vagus nerve activity can accompany lower resting heart rates.

    The vagus nerve extends from the brain stem to the atria of the heart, notes Circulation, an American Heart Association medical journal. At the heart, the vagus nerve releases the neurotransmitter acetylcholine onto the sinus node that controls the pace of the heartbeat. This produces relaxation and stimulates the dilation of blood vessels, counteracting the heightened awareness caused by the sympathetic system and allowing the heart rate to slow.

    Strong vagus nerve activity is responsible for the slow heart rates of many athletes, reports the Sarver Heart Center. However, an abnormally slow heart rate can indicate a heart defect in non-athletes and is a predictor of mortality, according to Circulation.


    'Powerful Predictor' of Sudden Death

    Heart rate during exercise and recovery is "a powerful predictor of the risk of sudden death" in seemingly healthy men, say researchers.

    Such tests could help doctors identify and treat high-risk men, they note.

    Smoking, obesity, diabetes, high blood pressure, high cholesterol, physical inactivity, and depression (especially in heart disease patients) have also been shown to be heart hazards.

    Many of those risk factors can be improved. For instance, exercise, stress control, and a healthy diet can help so can medications, when needed. Doctors can assess your risk and outline your options. Seek immediate help if you sense any heart problems.


    Riding Roller Coasters May Actually Be 'Death-defying' For People With Heart Disease

    The thrill of a roller coaster ride with its climbs, loops and dives can speed up the heart, sparking off an irregular heartbeat that could put individuals with heart disease at risk of having a cardiovascular event, according to new research reported at the American Heart Association's Scientific Sessions 2005.

    "Individuals who have suffered a heart attack, have heart disease or irregular heart rhythms should not ride a roller coaster," said Jurgen Kuschyk, M.D., a cardiologist at University Hospital in Mannheim, Germany. "The rising heart rate in riders with pre-existing heart disease could result in heart attack, irregular heart rhythms and possibly sudden cardiac death."

    A German study of 37 men and 18 women volunteers -- average age 28 -- found that some people who rode a roller coaster had an increased heart rate that could cause arrhythmias -- an irregular heart beat -- in some individuals. "The mental and physical stress from riding on the roller coaster was comparable to a fast game of squash or tennis," Kuschyk said. "For young healthy people there is no risk for heart attack and arrhythmias from riding a roller coaster."

    But people with high blood pressure, a previous heart attack, an implanted pacemaker or defibrillator, and others with proven heart disease, should not ride a roller coaster, researchers said.

    Kuschyk also suggested that operators of roller coasters have an external defibrillator on hand. "A lot of people don't know they have heart disease, yet they are riding roller coasters," he said.

    The heart rates of riders increased dramatically during and after the ride. Emotional stress appeared to be a strong contributing factor in the rise in heart rates of riders, especially in women who had higher maximum heart rates than men, researchers said.

    A continuous 12-channel Holter electrocardiogram was placed on participants. It recorded heart rates before, during and after the roller coaster ride.

    Thirty of the participants had never ridden a roller coaster before, while eight had a little experience and 17 had extensive experience. The roller coaster rides were performed on the "Expedition GeForce," at the Holiday Park in Hassioch, Germany. The ride involved a 120-second journey starting with a slow ascent to 62 meters (203.4 feet) above the ground, followed by a free fall and changes in gravity of 6 Gs in four seconds, and a maximum speed of 75 miles per hour. G-force is a measure of the magnitude of forces several times higher than the value of the earth's gravitational force.

    To rule out heart disease, all participants had a thorough physical examination before taking part in the study. At rest, before riding the roller coaster, participants' average heart rate was 91 beats per minutes (bpm), which is in the normal range. But after just over one minute on the ride, the riders' average maximum heart rates soared to an average 153 beats per minute.

    The average maximum heart rates of men and women riders were significantly different, Kuschyk said. Men had average heart rates of 148.5 bpm while women had average heart rates of almost 165 bpm. The highest average heart rate rise of 34 bpm occurred during the ascent. There were no significant differences in average heart rates in people with varying degrees of roller coaster experience.

    Before the study, the researchers thought the increased G-forces occurring when riders suddenly plummeted towards the ground would increase stress on the body and increase heart rate. "But the increased G-force didn't have too much of an effect on the heart rate," Kuschyk said. "The heart rate appeared to rise more from psychological stress and fear at the beginning as riders were climbing or reaching the top. This was surprising. Their heartbeat increased twice or triple the amount in the first part of the ride."

    Forty-four percent of the participants had marked sinus arrhythmias that lasted up to five minutes after the ride. One patient had an arrhythmia during the middle of the ride. Another experienced a self-terminating episode of atrial fibrillation, a rapid chaotic electrical activity in the upper chambers of the heart.

    "After the ride stopped, nearly half of the participants had irregular heartbeats or significant sinus arrhythmia, even though their heartbeat rates had returned to normal and were inside the range of a normal heartbeat rate," Kuschyk said.

    Co-authors are Karsten Hamm, M.D. Nina Schoene, M.D. Constanze Echternach, M.D. Christian Veltmann, M.D. Nevin Yilmaz, M.D. Timo Zepp, medical student Barbara Schuessler, medical student Christain Wolpert, M.D. and Martin Borggregfe, M.D., F.E.S.C.

    Story Source:

    Materials provided by American Heart Association. Note: Content may be edited for style and length.